BAGHDAD, IRAQ - DECEMBER 16: Comedian Robin Williams takes a picture with GI's camera as he entertains troops at Baghdad airport December 16, 2003 in Baghdad, Iraq. Williams poked fun at military life and world politics during his routine for hundreds of troops. (Photo by Chris Hondros/Getty Images)Comedian Robin Williams takes a picture with GI's camera as he entertains troops at Baghdad airport December 16, 2003 in Baghdad, Iraq. Williams poked fun at military life and world politics during his routine for hundreds of troops. (Photo by Chris Hondros/Getty Images)

WASHINGTON (CBSDC) — With the world struggling to digest the loss of Robin Williams, the entertainer, this real-life anecdote from comedian Rob Riggle can perhaps shed some light on the type of man Williams was, as a person.

Riggle, appearing on The Sports Junkies on 106.7 The Fan in Washington, D.C. on Tuesday, provided testimony from a United Service Organizations gala, held just a few years back in the nation’s capital.

“I’m just as sad as everybody else,” Riggle said. “It’s such a loss. I knew Robin. He and I did improv together at the Upright Citizens Brigade Theatre in Los Angeles, and just getting a chance to perform with him, live on stage, was one of the great thrills of my life.”

“And then he and I – we crossed paths several times – but I remember one time we were at the USO gala in Washington, D.C.,” he said. “If you go out and you do a tour with the USO, or you do anything for the USO, at the end of the year they have a big gala. They bring everyone back together, and I think that year I had gone to Iraq and done a comedy tour in Iraq. So I was at the gala with Robin. Robin had gone out and done some stuff for the USO and entertained the troops, and there were some other artists there – country music folks, and some NASCAR folks – a bunch of people were there.

“There was black tie event, really nice, and I think the president even spoke that night. But I remember, we were sitting there having dinner, I was sitting with Robin and the entertainment that night was, I believe, Brian McKnight, who was gonna come in and sing some songs. And his plane was either delayed or canceled, anyways; he wasn’t going to make the event.

“And they came up to our table and they said, ‘Hey Robin, we hate to put you on the spot, and feel free to say ‘no,’ but is there any way that you’d be willing to jump up and do like 10 minutes of entertainment, because our entertainment is not gonna make it?’ And Robin took another bite of salad and said, ‘Let’s go.’

“Jumped up on stage, and did 20 to 25 minutes of killer material that was topical. It was like, it wasn’t old stuff, it was like stuff that was going on right now. And I’m assuming he was improvising most of it, and he destroyed. The whole room was just electrified, and I remember sitting there watching him thinking, ‘Wow. That’s what it means to be Robin Williams. And that’s why he’s the best.’

“So I have many great thoughts, and I’m just as sad as everybody else.”